They're turning up in some unusual places, and questions about them are all over the map. Yes, drones are working their way into our lives more and more every day, causing reactions that range from bemusement to terror to anger.

In the wake of that, organizations as varied as sports leagues and law enforcement are developing procedures to address the flying devices.

So what are drones, what are they used for, and are they a cause for concern?

Drones, which sometimes are referred to as unmanned aircraft systems (UAS), are small aircraft that are operated remotely. They differ from traditional model airplanes in that they are able to hover and easily change direction and altitude, can fly autonomously and are usually computer-operated while remote-controlled aircraft are managed through radio transmitters.

How many are out there? That answer is as elusive as a grasp of regulations. The Dronelife website puts an estimate at more than 2 million, couching that with caution that the numbers are speculative. The number of privately owned drones is expected to grow dramatically in the coming years as the aircraft become more widely available and affordable.

According to FAA regulations announced earlier this year, they must fly below 500 feet, during daylight and within eyesight of the operator. Operators also must pass an aeronautical knowledge test, among other restrictions. The FAA is in the process of producing wider-ranging regulations for drones and has teamed with the Association for Unmanned Vehicle Systems International, the Academy of Model Aeronautics and the Small UAV Coalition to produce tips for users to know before they fly.

Drones frequently include cameras, which can provide a wide variety of uses — some of which can come into question.

This summer, a Kentucky man who noticed a drone hovering near his sunbathing daughter grabbed a shotgun from his house and knocked the UAS out of the sky. He was arrested and faces mischief and endangerment charges as well as the wrath of his neighbors, who suffered the destruction of the $1,800 device. Similar situations have arisen in New Jersey and California.

If that's not enough to cause concern, some drone owners go a bit further. For example, a teenage student in Connecticut attached a handgun to a drone and fired into the woods.

And then there are the threats of drones transporting contraband — including weapons — into prisons in the United States and in Great Britain. That led the U.K. government to issue an official warning to prison officials.

Those instances point out the question of whether citizens should be allowed to defend themselves against drones. However, it's illegal to shoot down drones, even though at least one company is marketing ammunition for that purpose.

But drones can be beneficial as well. The online shopping world is anticipating Amazon's use of drones for package delivery, further satisfying our instant-gratification culture.

High school and college football teams are excited about the possibility of using them during practice, giving coaches and players unique on-demand angles to study film of plays and formations after workouts. A UAS is valuable to athletes beyond football. As digital photography has advanced for athletic practice and preparation, drone use provides far more angles and details that coaches and athletes can easily break down and analyze, from skiing to cycling.

Surveyors and engineers have found that using drones can cut work from days to hours. And government entities and other organizations have struck promotional gold by using drones to film their highlights.

Whether the skies will soon be thick with buzzing drones remains to be seen. The near future might be rocky for operators as regulations and boundaries are being set. We're in a position to adapt to the continuing surge of the UAS, the same as we did for the smartphone.

One thing is certain: For the drone industry, things are looking up.